<?php
class Student{
    public $name;
    private $age;

    public function setAge($age){
        $this->age=$age;
    }
    public function getAge(){
        echo $this->name;
    }
}
$stu1 = new Student();
$stu2= new Student;
$stu1->name="zs";
echo $stu1->name;
$stu1->setAge(10);
$stu1->getAge();
$stu2->setAge(20);
$stu2->getAge();
// $stu1->age=10;

?>